1. Field of the Invention
The present invention relates to a liquid crystal display element in which pixel electrodes are divided into a multiple number of sub-pixel electrodes, a manufacturing method(s) thereof, and electronic devices (employing this element).
2. Technical Background
As described in Flat Panel Display 1994, in the article "The use of mass-produced panels using wide angle technology TFT for wide visual fields, as is required to make the leap to large size devices, is beginning to be seen in large size devices," (Dec. 10, 1993, Nikkei BP Company Publishing, page 166) various kinds of methods have been tested regarding wide angle visual field technology for liquid crystal panels. As representative of these methods, methods such as (1) a method for controlling liquid crystal orientation by techniques such as a rubbing process, and (2) a method for controlling voltage applied to liquid crystal molecules, utilizing a control capacitor, have been known.
The above method (1) equalizes the orientation of liquid crystal molecules in all directions. However, in this method, there are various problems, such as that the process becomes complicated, and that reproducibility is not good.
As for the above method (2), background art disclosed in, for example, JP Patent Laid-Open Application 4-348323, JP Patent Laid-Open Application 5-107556, and JP Patent Laid-Open Application 3-122621, is known. However, in this background technology, in order to form the control capacitor (control capacity) and an additional capacitor, it is necessary to add processes such as a special electrode forming process, a dielectric film (insulating layer) forming process, and the like, which create problems, such as process lengthening.
Similarly, as in the above method (2), background art, such as in JP Patent Laid-Open Application 6-102537, JP Patent Laid-Open Application 5-107556, JP Patent Laid-Open Application 6-95144, and JP Patent Laid-Open Application 5-289108, is known. In this background art, the control capacitor is formed using dielectric film, and so on, on top of a light blocking layer, and gate insulating film; and, pixel defects, line defects, and the like are caused if pinholes occur in the gate insulating film and dielectric film. Because of this, the film needs to be thickened, resulting in the capacitance per unit area of the control capacitor becoming small. If the capacitance per unit area is small, it is necessary to create the area on which the control capacitor is formed as large, in order to obtain the necessary capacitance. This worsens the aperture rate (light transmission characteristic) of the liquid crystal panel. In addition, if the control capacitor formation area is large, imperfections or the like also occur easily.
Moreover, in the liquid crystal panel, a holding capacitor (holding capacitance) for holding the electric load accumulated in the pixel electrode, is necessary. In the above method (2), the integration of this holding capacitor formation technology is a large technological problem.
The present invention is created to solve the above described technological problems. It is an object of the present invention to provide a liquid crystal display element, a manufacturing method thereof, and electronic devices, which can improve through a simple process the visual angle characteristics, and so on, of liquid crystal panels.